UNS S32760 Stainless Steel Duplex Plate High Strength For Extreme Corrosive Environments

UNS S32760 plate (also known as S32760 super duplex plate, 1.4501, Zeron 100, F55, or super duplex stainless steel plate) is a high-alloy super duplex stainless steel designed for service in extremely aggressive corrosive environments. Combining the best properties of austenitic and ferritic stainless steels, S32760 offers exceptional pitting and crevice corrosion resistance, high mechanical strength, and excellent resistance to stress corrosion cracking (SCC). It is the material of choice for offshore platforms, chemical processing, seawater systems, and desalination plants.
UNS S32760 is a super duplex stainless steel with a dual-phase microstructure (approximately 50% austenite / 50% ferrite). It is specifically formulated with additions of tungsten (W) and copper (Cu) to enhance its corrosion resistance beyond that of standard duplex grades like S31803 or S32205.

• PREN (Pitting Resistance Equivalent Number) > 40 – superior resistance to pitting and crevice corrosion

• High strength – approximately twice the yield strength of 316L stainless steel

• Excellent SCC resistance – ideal for chloride-containing environments

• Good weldability – maintains properties with proper filler metals

*PREN = %Cr + 3.3*(%Mo + 0.5*%W) + 16*%N ≈ 40+*

Q1: What is the difference between S32760 and S32205 (2205 duplex)?
A: S32760 is a super duplex grade with higher alloy content (Cr, Mo, W, Cu, N). It offers higher strength (≥550 MPa vs. ≥450 MPa) and better pitting resistance (PREN >40 vs. ~35). Choose S32760 for more aggressive environments like seawater or sour service.
Q2: Is S32760 weldable?
A: Yes. S32760 is weldable using standard processes (GTAW, SMAW, GMAW, SAW). Use matching filler metal (e.g., 25.10.4.L or S32760-specific electrodes). Preheat is generally not required, but interpass temperature should be kept below 150°C to maintain phase balance.
Q3: What is PREN and why does it matter?
A: PREN (Pitting Resistance Equivalent Number) predicts a stainless steel's resistance to pitting corrosion in chloride environments. S32760 has a PREN >40, making it highly resistant to pitting and crevice corrosion – ideal for seawater and chemical applications.
Q4: Does S32760 require heat treatment after welding?
A: Generally, no for most applications. However, solution annealing (1040–1100°C) followed by water quenching may be required for severely corrosive services or pressure vessel applications.
Q5: What certifications do you provide?
A: We supply EN 10204 Type 3.1 mill test certificates with every shipment. Type 3.2 or third-party inspection (SGS, BV, TUV, DNV) is available upon request.